During the development phases of portable, battery- or accumulator-operated power tools, comprehensive testing of prototypes is often carried out in the early stages already. Such testing normally focuses on recording important characteristic quantities of an electronic system and a motor of the power tool and its analysis. These data are required for an optimal configuration of the power tool in order to thereby achieve increased robustness of the power tool in field use.
Important variables of battery-operated power tools that must be monitored are, for instance: the motor current, the output battery current, the temperature of accumulator packs or cells, the temperature of the electronic system, and the electrical voltage.
These tests usually require time-consuming redesigns of the prototypes. For example, access to electrical lines of the prototype inside the housing requires the housing shells of the prototypes to be provided with through-holes via which diverse electrical measuring lines can be routed out of the prototype. In addition, it may be necessary to modify line lengths or routes of the internal motor control electronics so as to route them out of the unit. This makes it possible, for example, to measure a motor current or a battery current in the installed state of the power tool, using a current-measuring caliper. In addition, measuring lines may possibly need to be mounted directly on an electronics board, or temperature sensors may have to be fixed in place thereon.
In summary, all of the afore-mentioned measures may entail considerable interventions in and modifications of the power tool, which could have a disadvantageous effect on the internal marginal conditions of the power tool.